Apparatus for guiding a well tool being pumped out of a well into a laterally branching flow line



Nov. 28, 1967 J PENNINGTON 3,354,961

Filed May 26, 1965 APPARATUS FOR GUIDING A WELL TOOL BEING PUMPED OUT OF A WELL INTO A LATERALLY BRANCHING FLOW LINE IHIIHIH John V. Penn/091% INVENTOR.

' ATTOR/VEVJ BY 5M United States Patent APPARATUS FOR GUIDING A WELL TOOL BEING PUMPED OUT OF A WELL INTO A LATERALLY BRANCHING FLOW LINE John V. Pennington, Houston, Tex., assignor to Cameron Iron Works, Inc., Houston, Tex. Filed May 26, 1965, Ser. No. 458,957 6 Claims. (Cl. 166-75) ABSTRACT OF THE DISCLOSURE Apparatus is described for use with underwater wells to divert Well tools into a laterally branching flow line bore connected to the production bore, as they travel upwardly in the production bore of a well head. To divert the Well tool, permanent magnets are mounted on the well head and a magnetizable body is carried by the well tool. The magnets are located to pull the tool from its upward path toward the flow line bore so the tool will enter the flow line bore as it is being pumped out of the well.

This invention relates generally to apparatus for use with wells located at underwater levels, including an underwater wellhead that has a generally vertical production bore which affords vertical access to a well and a laterally branching flow line bore that is connected to and curves upwardly and outwardly from the side of the production bore and well tools which are adapted to be pumped through the flow line bore and the production bore into and out of the well. More particularly it relates to apparatus of this type having improved means for guiding the well tools from the production bore of the wellhead into the laterally branching flow line bore as the well tools travel upwardly through the production bore on their way out of the well.

The flow line bore is kept free of any sharp turns or bends to allow the well tools to be pumped into and out of the well to perform certain maintenance operations. In this type of wellhead, either the production bore continues vertically past its connection with the laterally curving flow line bore to afford vertical access to the well therethrough, or the flow line is connected to the upper end of the production bore and is removed when vertical access to the well through the production bore is desired. In the former, when well tools that have been pumped into the well through the flow line are being pumped out, they will tend to continue traveling vertically upward through the vertical production bore, bypass the entrance to the laterally branching flow line bore, and enter the vertical access portion of the production bore.

To prevent this, it has been proposed to position a deflector device in the production bore to deflect tools traveling vertically upwardly from the well into the laterally branching flow line bore. Such a deflector device will require apparatus for orienting it and for releasably locking it in place. In addition, the deflector will require special equipment to remove it, when, for example, it is desired to have vertical access to the well through the production bore in the wellhead. Further, the apparatus will be subject to mechanical failure, particularly after it has been in the well for a long period of time.

Therefore, it is an object of this invention to provide apparatus for guiding a well tool from the production bore of a wellhead into a laterally branching flow line bore that doesnt employ a deflector in the production bore.

It is another object of this invention to provide apparatus for guiding a well tool from the production bore of a wellhead into a laterally branching flow line bore that allows the free passage of well tools into the production bore through the vertical access portion thereof.

Other objects, advantages and features of this invention will be apparent to one skilled in the art from a consideration of this specification and attached drawings.

These objects are obtained in accordance with this invention by employing a magnetic field to guide the well tool from the production bore into the flow line bore as the tool travels upwardly out of the well. To obtain the desired movement, two bodies are used that are magnetically attracted to each other. One is carried by the well tool and one is located on the wellhead to cause the one carried by the well tool to move toward the flow line bore as the tool enters the common bore between the flow line bore and the production bore. By employing a magnetic field to divert the well tool, the bores of the wellhead can be kept free of obstructions.

The preferred embodiment of the inventon will now be described in detail in connection with the attached drawings in which,

FIGURE 1 is a view partially in elevation and partially in section of an underwater wellhead assembly illustrating in solid and dash lines two positions of a well tool as it moves upwardly out of the well and is diverted by the apparatus of this invention from the production bore into the flow line bore, said section being taken along line 1-1 of FIG. 2;

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1, and

FIG. 3 is a vertical sectional view, on an enlarged scale, taken along line 33 of FIG. 2.

The underwater wellhead assembly shown in FIG. 1 consists of a conductor or surface casing 11 which is usually jetted into the ground below earths surface 10 below the water until base plate assembly 12 attached thereto is in position adjacent to the earths surface. The conductor or surface casing is then anchored in position by cement layer 13 located between the conductor pipe and the walls of the hole formed when the conductor is jetted into place. Casing head assembly 14 is mounted on the top of conductor pipe 11 to support one or more additional strings of casing in the conventional manner. One additional casing string 15 is shown in the drawings. Christmas tree 16 is releasably connected to casing head 14 by releasable coupling 19 which preferably is of the type that allows the tree to be remotely attached and detached from the casing head. One connection of this type is shown and described in US. Patent No. 3,137,348.

Christmas tree 16 is provided with a vertically extending production bore 17 that is connected to tubing string 17a. Communication between the two is controlled by master valve 18. Swabbing valve 20 closes off the upper end of the production bore. Connected to the production bore intermediate its ends and curving upwardly and outwardly therefrom with its central axis tangent to the longitudinal axis of the production bore is flow line bore 21. Flow line bore 21 extends through flow wing 22 of the tree and is connected to flow line 23 by flow wing valve 24. Flow line 23 continues to curve until it is adjacent the earth surface under the water where it reserves its direction of curvature until it is extending generally horizontally along the earth surface. The flow line then extends horizontally along the earths surface below the water until it reaches a remote production facility which may be on a platform above the water or located on an adjacent shore. Whenever the flow line changes direction, it should do so with a radius of curvature such that pump-in well tools of the type available today, which are expected to be used, can pass therethrough.

Well tools that are run from the surface of the water into the well can be lowered vertically and pass through the production bore of the tree directly into the well tubing string 17a. Well tools lowered vertically from the surface of the water are run on wire lines and present no problem as to their recovery.

When well tools are pumped into and out of the well through the flow line, the fluid used to pump the tool in will either displace an equal volume of fluid into the formation of the well or an equal volume of fluid will need to be allowed to flow out of the well. For this purpose, and to also provide a connection to the well through which fluid can be pumped to pump the tool back out of the well, service bore 25 is provided in tree 16. The service bore is connected to service tubing string 25a through master valve 26. Valve 25b is located in the upper end of 'bore 25 to control the passage of fluid and well tools into and out of its upper end. Connected to the service bore intermediate its ends is service line bore 28a which curves upwardly and outwardly through service wing 28 with its central axis tangent to the longitudinal axis of the service bore and is connected to service line 29 through service wing valve 27. The service line continues curving in the same direction until it is running along the bottom parallel to the flow line. The curving of the service wing bore and service line may or may not be necessary depending upon whether or not well tools need to be pumped into and out of the service tubing string. When well tools are being pumped into and out of the service line bore, the fluid used can circulate into and out of the Well through flow line 23. To allow this communication between the service bore and the production and flow line bores of the tree, the service tubing string is connected to the production tubing string at a point in the well below the depth to which the well tools are pumped.

As stated above, in accordance with this invention, two bodies that are magnetically attracted to each other are employed to cause the well tool to enter the flow line bore at the intersection between the production bore and the flow line bore, as the well tool travels upwardly out of the well. One body is carried by the well tool; the other is mounted on the wellhead in position to attract the body on the Well tool and pull it into position to enter the flow line bore. One of the bodies, of course, must be magnetized in order to attract the other. Either body could perform that function, however, in the embodiment illustrated, the magnetized body is the one attached to the wellhead.

The body that is carried by the well tool comprises nose piece 32 of well tool guide 30. Preferably the nose piece contains a large quantity of ferromagnetic material so it will be readily attracted by the magnetized body on the wellhead to be described below. FIG. 1 shows two positions of well tool guide 30 as it travels upwardly through the common bore 31 formed at the interconnection of the production and flow line bores in Christmas tree 16. Besides rounded nose piece 32, the tool guide includes packer cup assembly 33 which is pivotally connected to the nose piece by ball and socket joint 34. The packer cup assembly includes two oppositely facing packer cups 35 and 36, which are mounted on mandrel 37. The tool guide is pivotally connected to the upper end of a well tool 38 through ball and socket joint 39. Only the upper end of well tool 38 is shown. It is also equipped with two oppositely facing packer cups on its lower end that comline with cups 35 and 36 to cause the guide and tool to move through the flow line and production bores with the fluid flowing therethrough. The two sets of cups are spaced far enough apart to span common bore 31.

The magnetized body on the wellhead includes a plu rality of bar magnets 40, mounted in pairs on the wellhead with the pairs spaced from each other along the flow line bore side of common bore 31. As shown in FIGS. 2 and 3, the magnets are located in the wall of Christmas tree 16 with their longitudinal axes extending radially from the flow line bore. The magnets of each pair are located with their axes generally perpendicular to the axis of the flow line bore and with poles of opposite polarity adjacent the bore. In this manner, a plurality of fields of magnetic flux are established in the common bore between the poles of the magnets that will attract nose piece 32 of the tool guide, pull it against the flow line side of the bore, and hold it against this side as it travels through the common bore, thereby causing the tool guide to enter the flow line bore.

To increase the strength of these magnetic fields, an elongated strip 41 of highly permeable material is mounted along the side of the wellhead in engagment with the poles of the bar magnets located away from the common bore. This, in effect, combines each pair of bar magnets into a horseshoe magnet having its poles located so as to attract any magnetizable material located in the common bore of the wellhead.

The magnets should be separted by a material having a low permeablity, such as Monel, to keep their magnetic fields concentrated in common bore 31. In the embodiment shown, the entire Christmas tree 16 is made from such material. If the tree is fabricated from material such as steel, however, only the portion of the tree surrounding the magnets need be made of such material.

Also, in the embodiment shown, a plurality of 'bar magnets 42 and elongated strip 43 of high permeability are positioned adjacent common bore 44 formed by service bore 25 and service flow line bore 28 in the same manner as magnets 40 and strip 41 to magnetically pull tool guide 30 back into service bore flow line should it be pumped into the service bore with a well tool for some reason.

From the foregoing it will be seen that this inventlon is one well adapted to attain all of the ends and objects hereinabove set forth, together with other advantages which are obvious and which are inherent to the apparatus.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims As many embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

The invention having been described, what is claimed is:

1. Apparatus for use in a well having a production bore for the passage of fluids and well tools, comprising a wellhead having a vertical bore adapted to form a continuation of the production bore, said vertical bore branching upwardly into a plurality of bores including a flow line bore, and magnetic means located on the wellhead for exerting a magnetic force on well tools of magnetizable material suflicient to divert such tools into the flow line bore as such tools travel upwardly in the vertical bore.

2. Apparatus for use with an underwater well located adjacent the bottom of a body of water, comprising a wellhead for installation on uch underwater well and having a production bore and a flow line bore connected to the production bore intermediate its ends, said production bore having a generally vertical longitudinal axis to allow well tools lowered from the surface of the water to pass freely therethrough into and out of such well, the axis of said flow line bore being curved upwardly from a point of substantial tangency with the longitudinal axis of the production bore at its intersection therewith to allow well tools to travel smoothly through the flow line bore into the production bore and thence into the well, said wellhead being made of a material having a low permeability for magnetic flux throughout the intersection of the two bores, a well tool for pumping into and out of such well through the flow line bore, and means including two magnetically mutually attracted bodies of ferromagnetic material, one of said bodies being permanently magnetized and carried by the well tool and the other being attached to the wellhead adjacent the intersection of the two bores, to guide the tool into the flow line bore as it is being pumped upwardly out of the well through the production bore.

3. Apparatus for use with an underwater well located adjacent the bottom of a body of water, comprising a wellhead for installation on such underwater well and having a production bore and a flow line bore connected to the production bore intermediate its ends, said production bore having a generally vertical longitudinal axis to allow well tools lowered from the surface of the water to pass freely therethrough into and out of such well, the axis of said flow line bore being curved upwardly from a. point of substantial tangency with the longitudinal axis of the production bore at its intersection therewith to allow well tools to travel smoothly through the flow line bore into the production bore and thence into the well, said wellhead being made of a material having a low permeability for magnetic flux throughout the intersection of the two bores, a well tool for pumping into and out of such well through the flow line bore, and means including two magnetically mutually attracted bodies of ferromagnetic material, one of said bodies being carried by the well tool and the other being permanently magnetized and attached to the wellhead adjacent the intersection of the two bores, to guide the tool into the flow line bore as it is being pumped upwardly out of the well through the production bore.

4. The combination of claim 3 in which the magnetized body of the wellhead comprises a plurality of pairs of bar magnets spaced along the wellhead on the flow line bore side at the intersection of the two bores, each pair beingarranged with poles of opposite polarity adjacent the bores and with a body of high permeability positioned adjacent their poles that are located away from the flow line bore to provide a highly permeable path between said latter poles.

5. Apparatus for use with an underwater well located adjacent the bottom of a body of water, comprising a wellhead for installation on such underwater well and having a production bore and a flow line bore connected to the production bore intermediate its ends, said production bore having a generally vertical longitudinal axis to allow well tools lowered from the surface of the water to pass freely therethrough into and out of such well, the axis of said flow line bore being curved upwardly from a point of substantial tangency with the longitudinal axis of the production bore at its intersection therewith to allow well tools to travel smoothly through the flow line bore into the production bore and thence into the well, said wellhead being made of a material having a low permeability for magnetic flux throughout the intersection of the two bores, a well tool for pumping into and out of such well through the flow line bore, and means including two magnetically mutually attracted bodies of ferromagnetic material, one of said bodies being pivotally attached to and carried by the well tool and the other being attached to the wellhead adjacent the intersection of the two bores, to guide the tool into the flow line bore as it be being pumped upwardly out of the well through the production bore.

6. Apparatus for use with an underwater well located adjacent the bottom of a body of water, comprising a wellhead for installation on such underwater well and having a production bore and a flow line bore connected to the production bore and intermediate its ends, said production bore having a generally vertical longitudinal axis to allow well tools lowered from the surface of the Water to pass freely therethrough into and out of such well, the axis of said flow line bore being curved upwardly from apoint of substantial tangency with the longitudinal axis of the production bore at its intersection therewith to allow well tools to travel smoothly through the flow line bore into the production bore and thence into the well, and means including a body of magnetized material attached to the wellhead at the intersection of the two bores to magnetically attract a body of ferromagnetic material carried by a well tool and pull the body toward the flow line bore to guide the tool into the flow line bore as the tool travels upwardly out of the well through the production bore, said body comprising a plurality of pairs of bar magnets spaced along the wellhead on the flow line bore side at the intersection of the two bores, each pair being arranged with poles of opposite polarity adjacent the bores and with a body of high permeability positioned adjacent their poles that are located away from the flow line bore to provide a highly permeable path between said latter poles.

References Cited UNITED STATES PATENTS 2,664,162 12/1953 Howard et a1. 166-65 3,064,735 11/1962 Bauer et al 166.6 3,055,429 9/1962 Tausch et al. 166-.5 3,105,551 10/1963 Ehlert 16665 3,139,932 7/1964 Johnson 166.6

CHARLES E. OCONNELL, Primary Examiner. RICHARD E. FAVREAU, Assistant Examiner. 

1. APPARATUS FOR USE IN A WELL HAVING A PRODUCTION BORE FOR THE PASSAGE OF FLUIDS AND WELL TOOLS, COMPRISING A WELLHEAD HAVING A VERTICAL BORE ADAPTED TO FORM A CONTINUATION OF THE PRODUCTION BORE, SAID VERTICAL BORE BRANCHING UPWARDLY INTO A PLURALITY OF BORES INCLUDING A FLOW LINE BORE, AND MAGNETIC MEANS LOCATED ON THE WELLHEAD FOR EXERTING AN MAGNETIC FORCE ON WELL TOOLS OF MAGNETIZABLE MATERIAL SUFFICIENT TO DIVERT SUCH TOOLS INTO THE FLOW LINE BORE AS SUCH TOOLS TRAVEL UPWARDLY IN THE VERTICAL BORE. 